1 /* bpf_jit_comp.c : BPF JIT compiler 2 * 3 * Copyright (C) 2011-2013 Eric Dumazet (eric.dumazet@gmail.com) 4 * Internal BPF Copyright (c) 2011-2014 PLUMgrid, http://plumgrid.com 5 * 6 * This program is free software; you can redistribute it and/or 7 * modify it under the terms of the GNU General Public License 8 * as published by the Free Software Foundation; version 2 9 * of the License. 10 */ 11 #include <linux/netdevice.h> 12 #include <linux/filter.h> 13 #include <linux/if_vlan.h> 14 #include <asm/cacheflush.h> 15 #include <asm/set_memory.h> 16 #include <linux/bpf.h> 17 18 int bpf_jit_enable __read_mostly; 19 20 /* 21 * assembly code in arch/x86/net/bpf_jit.S 22 */ 23 extern u8 sk_load_word[], sk_load_half[], sk_load_byte[]; 24 extern u8 sk_load_word_positive_offset[], sk_load_half_positive_offset[]; 25 extern u8 sk_load_byte_positive_offset[]; 26 extern u8 sk_load_word_negative_offset[], sk_load_half_negative_offset[]; 27 extern u8 sk_load_byte_negative_offset[]; 28 29 static u8 *emit_code(u8 *ptr, u32 bytes, unsigned int len) 30 { 31 if (len == 1) 32 *ptr = bytes; 33 else if (len == 2) 34 *(u16 *)ptr = bytes; 35 else { 36 *(u32 *)ptr = bytes; 37 barrier(); 38 } 39 return ptr + len; 40 } 41 42 #define EMIT(bytes, len) \ 43 do { prog = emit_code(prog, bytes, len); cnt += len; } while (0) 44 45 #define EMIT1(b1) EMIT(b1, 1) 46 #define EMIT2(b1, b2) EMIT((b1) + ((b2) << 8), 2) 47 #define EMIT3(b1, b2, b3) EMIT((b1) + ((b2) << 8) + ((b3) << 16), 3) 48 #define EMIT4(b1, b2, b3, b4) EMIT((b1) + ((b2) << 8) + ((b3) << 16) + ((b4) << 24), 4) 49 #define EMIT1_off32(b1, off) \ 50 do {EMIT1(b1); EMIT(off, 4); } while (0) 51 #define EMIT2_off32(b1, b2, off) \ 52 do {EMIT2(b1, b2); EMIT(off, 4); } while (0) 53 #define EMIT3_off32(b1, b2, b3, off) \ 54 do {EMIT3(b1, b2, b3); EMIT(off, 4); } while (0) 55 #define EMIT4_off32(b1, b2, b3, b4, off) \ 56 do {EMIT4(b1, b2, b3, b4); EMIT(off, 4); } while (0) 57 58 static bool is_imm8(int value) 59 { 60 return value <= 127 && value >= -128; 61 } 62 63 static bool is_simm32(s64 value) 64 { 65 return value == (s64) (s32) value; 66 } 67 68 /* mov dst, src */ 69 #define EMIT_mov(DST, SRC) \ 70 do {if (DST != SRC) \ 71 EMIT3(add_2mod(0x48, DST, SRC), 0x89, add_2reg(0xC0, DST, SRC)); \ 72 } while (0) 73 74 static int bpf_size_to_x86_bytes(int bpf_size) 75 { 76 if (bpf_size == BPF_W) 77 return 4; 78 else if (bpf_size == BPF_H) 79 return 2; 80 else if (bpf_size == BPF_B) 81 return 1; 82 else if (bpf_size == BPF_DW) 83 return 4; /* imm32 */ 84 else 85 return 0; 86 } 87 88 /* list of x86 cond jumps opcodes (. + s8) 89 * Add 0x10 (and an extra 0x0f) to generate far jumps (. + s32) 90 */ 91 #define X86_JB 0x72 92 #define X86_JAE 0x73 93 #define X86_JE 0x74 94 #define X86_JNE 0x75 95 #define X86_JBE 0x76 96 #define X86_JA 0x77 97 #define X86_JL 0x7C 98 #define X86_JGE 0x7D 99 #define X86_JLE 0x7E 100 #define X86_JG 0x7F 101 102 static void bpf_flush_icache(void *start, void *end) 103 { 104 mm_segment_t old_fs = get_fs(); 105 106 set_fs(KERNEL_DS); 107 smp_wmb(); 108 flush_icache_range((unsigned long)start, (unsigned long)end); 109 set_fs(old_fs); 110 } 111 112 #define CHOOSE_LOAD_FUNC(K, func) \ 113 ((int)K < 0 ? ((int)K >= SKF_LL_OFF ? func##_negative_offset : func) : func##_positive_offset) 114 115 /* pick a register outside of BPF range for JIT internal work */ 116 #define AUX_REG (MAX_BPF_JIT_REG + 1) 117 118 /* The following table maps BPF registers to x64 registers. 119 * 120 * x64 register r12 is unused, since if used as base address 121 * register in load/store instructions, it always needs an 122 * extra byte of encoding and is callee saved. 123 * 124 * r9 caches skb->len - skb->data_len 125 * r10 caches skb->data, and used for blinding (if enabled) 126 */ 127 static const int reg2hex[] = { 128 [BPF_REG_0] = 0, /* rax */ 129 [BPF_REG_1] = 7, /* rdi */ 130 [BPF_REG_2] = 6, /* rsi */ 131 [BPF_REG_3] = 2, /* rdx */ 132 [BPF_REG_4] = 1, /* rcx */ 133 [BPF_REG_5] = 0, /* r8 */ 134 [BPF_REG_6] = 3, /* rbx callee saved */ 135 [BPF_REG_7] = 5, /* r13 callee saved */ 136 [BPF_REG_8] = 6, /* r14 callee saved */ 137 [BPF_REG_9] = 7, /* r15 callee saved */ 138 [BPF_REG_FP] = 5, /* rbp readonly */ 139 [BPF_REG_AX] = 2, /* r10 temp register */ 140 [AUX_REG] = 3, /* r11 temp register */ 141 }; 142 143 /* is_ereg() == true if BPF register 'reg' maps to x64 r8..r15 144 * which need extra byte of encoding. 145 * rax,rcx,...,rbp have simpler encoding 146 */ 147 static bool is_ereg(u32 reg) 148 { 149 return (1 << reg) & (BIT(BPF_REG_5) | 150 BIT(AUX_REG) | 151 BIT(BPF_REG_7) | 152 BIT(BPF_REG_8) | 153 BIT(BPF_REG_9) | 154 BIT(BPF_REG_AX)); 155 } 156 157 /* add modifiers if 'reg' maps to x64 registers r8..r15 */ 158 static u8 add_1mod(u8 byte, u32 reg) 159 { 160 if (is_ereg(reg)) 161 byte |= 1; 162 return byte; 163 } 164 165 static u8 add_2mod(u8 byte, u32 r1, u32 r2) 166 { 167 if (is_ereg(r1)) 168 byte |= 1; 169 if (is_ereg(r2)) 170 byte |= 4; 171 return byte; 172 } 173 174 /* encode 'dst_reg' register into x64 opcode 'byte' */ 175 static u8 add_1reg(u8 byte, u32 dst_reg) 176 { 177 return byte + reg2hex[dst_reg]; 178 } 179 180 /* encode 'dst_reg' and 'src_reg' registers into x64 opcode 'byte' */ 181 static u8 add_2reg(u8 byte, u32 dst_reg, u32 src_reg) 182 { 183 return byte + reg2hex[dst_reg] + (reg2hex[src_reg] << 3); 184 } 185 186 static void jit_fill_hole(void *area, unsigned int size) 187 { 188 /* fill whole space with int3 instructions */ 189 memset(area, 0xcc, size); 190 } 191 192 struct jit_context { 193 int cleanup_addr; /* epilogue code offset */ 194 bool seen_ld_abs; 195 bool seen_ax_reg; 196 }; 197 198 /* maximum number of bytes emitted while JITing one eBPF insn */ 199 #define BPF_MAX_INSN_SIZE 128 200 #define BPF_INSN_SAFETY 64 201 202 #define AUX_STACK_SPACE \ 203 (32 /* space for rbx, r13, r14, r15 */ + \ 204 8 /* space for skb_copy_bits() buffer */) 205 206 #define PROLOGUE_SIZE 37 207 208 /* emit x64 prologue code for BPF program and check it's size. 209 * bpf_tail_call helper will skip it while jumping into another program 210 */ 211 static void emit_prologue(u8 **pprog, u32 stack_depth) 212 { 213 u8 *prog = *pprog; 214 int cnt = 0; 215 216 EMIT1(0x55); /* push rbp */ 217 EMIT3(0x48, 0x89, 0xE5); /* mov rbp,rsp */ 218 219 /* sub rsp, rounded_stack_depth + AUX_STACK_SPACE */ 220 EMIT3_off32(0x48, 0x81, 0xEC, 221 round_up(stack_depth, 8) + AUX_STACK_SPACE); 222 223 /* sub rbp, AUX_STACK_SPACE */ 224 EMIT4(0x48, 0x83, 0xED, AUX_STACK_SPACE); 225 226 /* all classic BPF filters use R6(rbx) save it */ 227 228 /* mov qword ptr [rbp+0],rbx */ 229 EMIT4(0x48, 0x89, 0x5D, 0); 230 231 /* bpf_convert_filter() maps classic BPF register X to R7 and uses R8 232 * as temporary, so all tcpdump filters need to spill/fill R7(r13) and 233 * R8(r14). R9(r15) spill could be made conditional, but there is only 234 * one 'bpf_error' return path out of helper functions inside bpf_jit.S 235 * The overhead of extra spill is negligible for any filter other 236 * than synthetic ones. Therefore not worth adding complexity. 237 */ 238 239 /* mov qword ptr [rbp+8],r13 */ 240 EMIT4(0x4C, 0x89, 0x6D, 8); 241 /* mov qword ptr [rbp+16],r14 */ 242 EMIT4(0x4C, 0x89, 0x75, 16); 243 /* mov qword ptr [rbp+24],r15 */ 244 EMIT4(0x4C, 0x89, 0x7D, 24); 245 246 /* Clear the tail call counter (tail_call_cnt): for eBPF tail calls 247 * we need to reset the counter to 0. It's done in two instructions, 248 * resetting rax register to 0 (xor on eax gets 0 extended), and 249 * moving it to the counter location. 250 */ 251 252 /* xor eax, eax */ 253 EMIT2(0x31, 0xc0); 254 /* mov qword ptr [rbp+32], rax */ 255 EMIT4(0x48, 0x89, 0x45, 32); 256 257 BUILD_BUG_ON(cnt != PROLOGUE_SIZE); 258 *pprog = prog; 259 } 260 261 /* generate the following code: 262 * ... bpf_tail_call(void *ctx, struct bpf_array *array, u64 index) ... 263 * if (index >= array->map.max_entries) 264 * goto out; 265 * if (++tail_call_cnt > MAX_TAIL_CALL_CNT) 266 * goto out; 267 * prog = array->ptrs[index]; 268 * if (prog == NULL) 269 * goto out; 270 * goto *(prog->bpf_func + prologue_size); 271 * out: 272 */ 273 static void emit_bpf_tail_call(u8 **pprog) 274 { 275 u8 *prog = *pprog; 276 int label1, label2, label3; 277 int cnt = 0; 278 279 /* rdi - pointer to ctx 280 * rsi - pointer to bpf_array 281 * rdx - index in bpf_array 282 */ 283 284 /* if (index >= array->map.max_entries) 285 * goto out; 286 */ 287 EMIT4(0x48, 0x8B, 0x46, /* mov rax, qword ptr [rsi + 16] */ 288 offsetof(struct bpf_array, map.max_entries)); 289 EMIT3(0x48, 0x39, 0xD0); /* cmp rax, rdx */ 290 #define OFFSET1 43 /* number of bytes to jump */ 291 EMIT2(X86_JBE, OFFSET1); /* jbe out */ 292 label1 = cnt; 293 294 /* if (tail_call_cnt > MAX_TAIL_CALL_CNT) 295 * goto out; 296 */ 297 EMIT2_off32(0x8B, 0x85, 36); /* mov eax, dword ptr [rbp + 36] */ 298 EMIT3(0x83, 0xF8, MAX_TAIL_CALL_CNT); /* cmp eax, MAX_TAIL_CALL_CNT */ 299 #define OFFSET2 32 300 EMIT2(X86_JA, OFFSET2); /* ja out */ 301 label2 = cnt; 302 EMIT3(0x83, 0xC0, 0x01); /* add eax, 1 */ 303 EMIT2_off32(0x89, 0x85, 36); /* mov dword ptr [rbp + 36], eax */ 304 305 /* prog = array->ptrs[index]; */ 306 EMIT4_off32(0x48, 0x8B, 0x84, 0xD6, /* mov rax, [rsi + rdx * 8 + offsetof(...)] */ 307 offsetof(struct bpf_array, ptrs)); 308 309 /* if (prog == NULL) 310 * goto out; 311 */ 312 EMIT3(0x48, 0x85, 0xC0); /* test rax,rax */ 313 #define OFFSET3 10 314 EMIT2(X86_JE, OFFSET3); /* je out */ 315 label3 = cnt; 316 317 /* goto *(prog->bpf_func + prologue_size); */ 318 EMIT4(0x48, 0x8B, 0x40, /* mov rax, qword ptr [rax + 32] */ 319 offsetof(struct bpf_prog, bpf_func)); 320 EMIT4(0x48, 0x83, 0xC0, PROLOGUE_SIZE); /* add rax, prologue_size */ 321 322 /* now we're ready to jump into next BPF program 323 * rdi == ctx (1st arg) 324 * rax == prog->bpf_func + prologue_size 325 */ 326 EMIT2(0xFF, 0xE0); /* jmp rax */ 327 328 /* out: */ 329 BUILD_BUG_ON(cnt - label1 != OFFSET1); 330 BUILD_BUG_ON(cnt - label2 != OFFSET2); 331 BUILD_BUG_ON(cnt - label3 != OFFSET3); 332 *pprog = prog; 333 } 334 335 336 static void emit_load_skb_data_hlen(u8 **pprog) 337 { 338 u8 *prog = *pprog; 339 int cnt = 0; 340 341 /* r9d = skb->len - skb->data_len (headlen) 342 * r10 = skb->data 343 */ 344 /* mov %r9d, off32(%rdi) */ 345 EMIT3_off32(0x44, 0x8b, 0x8f, offsetof(struct sk_buff, len)); 346 347 /* sub %r9d, off32(%rdi) */ 348 EMIT3_off32(0x44, 0x2b, 0x8f, offsetof(struct sk_buff, data_len)); 349 350 /* mov %r10, off32(%rdi) */ 351 EMIT3_off32(0x4c, 0x8b, 0x97, offsetof(struct sk_buff, data)); 352 *pprog = prog; 353 } 354 355 static int do_jit(struct bpf_prog *bpf_prog, int *addrs, u8 *image, 356 int oldproglen, struct jit_context *ctx) 357 { 358 struct bpf_insn *insn = bpf_prog->insnsi; 359 int insn_cnt = bpf_prog->len; 360 bool seen_ld_abs = ctx->seen_ld_abs | (oldproglen == 0); 361 bool seen_ax_reg = ctx->seen_ax_reg | (oldproglen == 0); 362 bool seen_exit = false; 363 u8 temp[BPF_MAX_INSN_SIZE + BPF_INSN_SAFETY]; 364 int i, cnt = 0; 365 int proglen = 0; 366 u8 *prog = temp; 367 368 emit_prologue(&prog, bpf_prog->aux->stack_depth); 369 370 if (seen_ld_abs) 371 emit_load_skb_data_hlen(&prog); 372 373 for (i = 0; i < insn_cnt; i++, insn++) { 374 const s32 imm32 = insn->imm; 375 u32 dst_reg = insn->dst_reg; 376 u32 src_reg = insn->src_reg; 377 u8 b1 = 0, b2 = 0, b3 = 0; 378 s64 jmp_offset; 379 u8 jmp_cond; 380 bool reload_skb_data; 381 int ilen; 382 u8 *func; 383 384 if (dst_reg == BPF_REG_AX || src_reg == BPF_REG_AX) 385 ctx->seen_ax_reg = seen_ax_reg = true; 386 387 switch (insn->code) { 388 /* ALU */ 389 case BPF_ALU | BPF_ADD | BPF_X: 390 case BPF_ALU | BPF_SUB | BPF_X: 391 case BPF_ALU | BPF_AND | BPF_X: 392 case BPF_ALU | BPF_OR | BPF_X: 393 case BPF_ALU | BPF_XOR | BPF_X: 394 case BPF_ALU64 | BPF_ADD | BPF_X: 395 case BPF_ALU64 | BPF_SUB | BPF_X: 396 case BPF_ALU64 | BPF_AND | BPF_X: 397 case BPF_ALU64 | BPF_OR | BPF_X: 398 case BPF_ALU64 | BPF_XOR | BPF_X: 399 switch (BPF_OP(insn->code)) { 400 case BPF_ADD: b2 = 0x01; break; 401 case BPF_SUB: b2 = 0x29; break; 402 case BPF_AND: b2 = 0x21; break; 403 case BPF_OR: b2 = 0x09; break; 404 case BPF_XOR: b2 = 0x31; break; 405 } 406 if (BPF_CLASS(insn->code) == BPF_ALU64) 407 EMIT1(add_2mod(0x48, dst_reg, src_reg)); 408 else if (is_ereg(dst_reg) || is_ereg(src_reg)) 409 EMIT1(add_2mod(0x40, dst_reg, src_reg)); 410 EMIT2(b2, add_2reg(0xC0, dst_reg, src_reg)); 411 break; 412 413 /* mov dst, src */ 414 case BPF_ALU64 | BPF_MOV | BPF_X: 415 EMIT_mov(dst_reg, src_reg); 416 break; 417 418 /* mov32 dst, src */ 419 case BPF_ALU | BPF_MOV | BPF_X: 420 if (is_ereg(dst_reg) || is_ereg(src_reg)) 421 EMIT1(add_2mod(0x40, dst_reg, src_reg)); 422 EMIT2(0x89, add_2reg(0xC0, dst_reg, src_reg)); 423 break; 424 425 /* neg dst */ 426 case BPF_ALU | BPF_NEG: 427 case BPF_ALU64 | BPF_NEG: 428 if (BPF_CLASS(insn->code) == BPF_ALU64) 429 EMIT1(add_1mod(0x48, dst_reg)); 430 else if (is_ereg(dst_reg)) 431 EMIT1(add_1mod(0x40, dst_reg)); 432 EMIT2(0xF7, add_1reg(0xD8, dst_reg)); 433 break; 434 435 case BPF_ALU | BPF_ADD | BPF_K: 436 case BPF_ALU | BPF_SUB | BPF_K: 437 case BPF_ALU | BPF_AND | BPF_K: 438 case BPF_ALU | BPF_OR | BPF_K: 439 case BPF_ALU | BPF_XOR | BPF_K: 440 case BPF_ALU64 | BPF_ADD | BPF_K: 441 case BPF_ALU64 | BPF_SUB | BPF_K: 442 case BPF_ALU64 | BPF_AND | BPF_K: 443 case BPF_ALU64 | BPF_OR | BPF_K: 444 case BPF_ALU64 | BPF_XOR | BPF_K: 445 if (BPF_CLASS(insn->code) == BPF_ALU64) 446 EMIT1(add_1mod(0x48, dst_reg)); 447 else if (is_ereg(dst_reg)) 448 EMIT1(add_1mod(0x40, dst_reg)); 449 450 switch (BPF_OP(insn->code)) { 451 case BPF_ADD: b3 = 0xC0; break; 452 case BPF_SUB: b3 = 0xE8; break; 453 case BPF_AND: b3 = 0xE0; break; 454 case BPF_OR: b3 = 0xC8; break; 455 case BPF_XOR: b3 = 0xF0; break; 456 } 457 458 if (is_imm8(imm32)) 459 EMIT3(0x83, add_1reg(b3, dst_reg), imm32); 460 else 461 EMIT2_off32(0x81, add_1reg(b3, dst_reg), imm32); 462 break; 463 464 case BPF_ALU64 | BPF_MOV | BPF_K: 465 /* optimization: if imm32 is positive, 466 * use 'mov eax, imm32' (which zero-extends imm32) 467 * to save 2 bytes 468 */ 469 if (imm32 < 0) { 470 /* 'mov rax, imm32' sign extends imm32 */ 471 b1 = add_1mod(0x48, dst_reg); 472 b2 = 0xC7; 473 b3 = 0xC0; 474 EMIT3_off32(b1, b2, add_1reg(b3, dst_reg), imm32); 475 break; 476 } 477 478 case BPF_ALU | BPF_MOV | BPF_K: 479 /* optimization: if imm32 is zero, use 'xor <dst>,<dst>' 480 * to save 3 bytes. 481 */ 482 if (imm32 == 0) { 483 if (is_ereg(dst_reg)) 484 EMIT1(add_2mod(0x40, dst_reg, dst_reg)); 485 b2 = 0x31; /* xor */ 486 b3 = 0xC0; 487 EMIT2(b2, add_2reg(b3, dst_reg, dst_reg)); 488 break; 489 } 490 491 /* mov %eax, imm32 */ 492 if (is_ereg(dst_reg)) 493 EMIT1(add_1mod(0x40, dst_reg)); 494 EMIT1_off32(add_1reg(0xB8, dst_reg), imm32); 495 break; 496 497 case BPF_LD | BPF_IMM | BPF_DW: 498 /* optimization: if imm64 is zero, use 'xor <dst>,<dst>' 499 * to save 7 bytes. 500 */ 501 if (insn[0].imm == 0 && insn[1].imm == 0) { 502 b1 = add_2mod(0x48, dst_reg, dst_reg); 503 b2 = 0x31; /* xor */ 504 b3 = 0xC0; 505 EMIT3(b1, b2, add_2reg(b3, dst_reg, dst_reg)); 506 507 insn++; 508 i++; 509 break; 510 } 511 512 /* movabsq %rax, imm64 */ 513 EMIT2(add_1mod(0x48, dst_reg), add_1reg(0xB8, dst_reg)); 514 EMIT(insn[0].imm, 4); 515 EMIT(insn[1].imm, 4); 516 517 insn++; 518 i++; 519 break; 520 521 /* dst %= src, dst /= src, dst %= imm32, dst /= imm32 */ 522 case BPF_ALU | BPF_MOD | BPF_X: 523 case BPF_ALU | BPF_DIV | BPF_X: 524 case BPF_ALU | BPF_MOD | BPF_K: 525 case BPF_ALU | BPF_DIV | BPF_K: 526 case BPF_ALU64 | BPF_MOD | BPF_X: 527 case BPF_ALU64 | BPF_DIV | BPF_X: 528 case BPF_ALU64 | BPF_MOD | BPF_K: 529 case BPF_ALU64 | BPF_DIV | BPF_K: 530 EMIT1(0x50); /* push rax */ 531 EMIT1(0x52); /* push rdx */ 532 533 if (BPF_SRC(insn->code) == BPF_X) 534 /* mov r11, src_reg */ 535 EMIT_mov(AUX_REG, src_reg); 536 else 537 /* mov r11, imm32 */ 538 EMIT3_off32(0x49, 0xC7, 0xC3, imm32); 539 540 /* mov rax, dst_reg */ 541 EMIT_mov(BPF_REG_0, dst_reg); 542 543 /* xor edx, edx 544 * equivalent to 'xor rdx, rdx', but one byte less 545 */ 546 EMIT2(0x31, 0xd2); 547 548 if (BPF_SRC(insn->code) == BPF_X) { 549 /* if (src_reg == 0) return 0 */ 550 551 /* cmp r11, 0 */ 552 EMIT4(0x49, 0x83, 0xFB, 0x00); 553 554 /* jne .+9 (skip over pop, pop, xor and jmp) */ 555 EMIT2(X86_JNE, 1 + 1 + 2 + 5); 556 EMIT1(0x5A); /* pop rdx */ 557 EMIT1(0x58); /* pop rax */ 558 EMIT2(0x31, 0xc0); /* xor eax, eax */ 559 560 /* jmp cleanup_addr 561 * addrs[i] - 11, because there are 11 bytes 562 * after this insn: div, mov, pop, pop, mov 563 */ 564 jmp_offset = ctx->cleanup_addr - (addrs[i] - 11); 565 EMIT1_off32(0xE9, jmp_offset); 566 } 567 568 if (BPF_CLASS(insn->code) == BPF_ALU64) 569 /* div r11 */ 570 EMIT3(0x49, 0xF7, 0xF3); 571 else 572 /* div r11d */ 573 EMIT3(0x41, 0xF7, 0xF3); 574 575 if (BPF_OP(insn->code) == BPF_MOD) 576 /* mov r11, rdx */ 577 EMIT3(0x49, 0x89, 0xD3); 578 else 579 /* mov r11, rax */ 580 EMIT3(0x49, 0x89, 0xC3); 581 582 EMIT1(0x5A); /* pop rdx */ 583 EMIT1(0x58); /* pop rax */ 584 585 /* mov dst_reg, r11 */ 586 EMIT_mov(dst_reg, AUX_REG); 587 break; 588 589 case BPF_ALU | BPF_MUL | BPF_K: 590 case BPF_ALU | BPF_MUL | BPF_X: 591 case BPF_ALU64 | BPF_MUL | BPF_K: 592 case BPF_ALU64 | BPF_MUL | BPF_X: 593 EMIT1(0x50); /* push rax */ 594 EMIT1(0x52); /* push rdx */ 595 596 /* mov r11, dst_reg */ 597 EMIT_mov(AUX_REG, dst_reg); 598 599 if (BPF_SRC(insn->code) == BPF_X) 600 /* mov rax, src_reg */ 601 EMIT_mov(BPF_REG_0, src_reg); 602 else 603 /* mov rax, imm32 */ 604 EMIT3_off32(0x48, 0xC7, 0xC0, imm32); 605 606 if (BPF_CLASS(insn->code) == BPF_ALU64) 607 EMIT1(add_1mod(0x48, AUX_REG)); 608 else if (is_ereg(AUX_REG)) 609 EMIT1(add_1mod(0x40, AUX_REG)); 610 /* mul(q) r11 */ 611 EMIT2(0xF7, add_1reg(0xE0, AUX_REG)); 612 613 /* mov r11, rax */ 614 EMIT_mov(AUX_REG, BPF_REG_0); 615 616 EMIT1(0x5A); /* pop rdx */ 617 EMIT1(0x58); /* pop rax */ 618 619 /* mov dst_reg, r11 */ 620 EMIT_mov(dst_reg, AUX_REG); 621 break; 622 623 /* shifts */ 624 case BPF_ALU | BPF_LSH | BPF_K: 625 case BPF_ALU | BPF_RSH | BPF_K: 626 case BPF_ALU | BPF_ARSH | BPF_K: 627 case BPF_ALU64 | BPF_LSH | BPF_K: 628 case BPF_ALU64 | BPF_RSH | BPF_K: 629 case BPF_ALU64 | BPF_ARSH | BPF_K: 630 if (BPF_CLASS(insn->code) == BPF_ALU64) 631 EMIT1(add_1mod(0x48, dst_reg)); 632 else if (is_ereg(dst_reg)) 633 EMIT1(add_1mod(0x40, dst_reg)); 634 635 switch (BPF_OP(insn->code)) { 636 case BPF_LSH: b3 = 0xE0; break; 637 case BPF_RSH: b3 = 0xE8; break; 638 case BPF_ARSH: b3 = 0xF8; break; 639 } 640 EMIT3(0xC1, add_1reg(b3, dst_reg), imm32); 641 break; 642 643 case BPF_ALU | BPF_LSH | BPF_X: 644 case BPF_ALU | BPF_RSH | BPF_X: 645 case BPF_ALU | BPF_ARSH | BPF_X: 646 case BPF_ALU64 | BPF_LSH | BPF_X: 647 case BPF_ALU64 | BPF_RSH | BPF_X: 648 case BPF_ALU64 | BPF_ARSH | BPF_X: 649 650 /* check for bad case when dst_reg == rcx */ 651 if (dst_reg == BPF_REG_4) { 652 /* mov r11, dst_reg */ 653 EMIT_mov(AUX_REG, dst_reg); 654 dst_reg = AUX_REG; 655 } 656 657 if (src_reg != BPF_REG_4) { /* common case */ 658 EMIT1(0x51); /* push rcx */ 659 660 /* mov rcx, src_reg */ 661 EMIT_mov(BPF_REG_4, src_reg); 662 } 663 664 /* shl %rax, %cl | shr %rax, %cl | sar %rax, %cl */ 665 if (BPF_CLASS(insn->code) == BPF_ALU64) 666 EMIT1(add_1mod(0x48, dst_reg)); 667 else if (is_ereg(dst_reg)) 668 EMIT1(add_1mod(0x40, dst_reg)); 669 670 switch (BPF_OP(insn->code)) { 671 case BPF_LSH: b3 = 0xE0; break; 672 case BPF_RSH: b3 = 0xE8; break; 673 case BPF_ARSH: b3 = 0xF8; break; 674 } 675 EMIT2(0xD3, add_1reg(b3, dst_reg)); 676 677 if (src_reg != BPF_REG_4) 678 EMIT1(0x59); /* pop rcx */ 679 680 if (insn->dst_reg == BPF_REG_4) 681 /* mov dst_reg, r11 */ 682 EMIT_mov(insn->dst_reg, AUX_REG); 683 break; 684 685 case BPF_ALU | BPF_END | BPF_FROM_BE: 686 switch (imm32) { 687 case 16: 688 /* emit 'ror %ax, 8' to swap lower 2 bytes */ 689 EMIT1(0x66); 690 if (is_ereg(dst_reg)) 691 EMIT1(0x41); 692 EMIT3(0xC1, add_1reg(0xC8, dst_reg), 8); 693 694 /* emit 'movzwl eax, ax' */ 695 if (is_ereg(dst_reg)) 696 EMIT3(0x45, 0x0F, 0xB7); 697 else 698 EMIT2(0x0F, 0xB7); 699 EMIT1(add_2reg(0xC0, dst_reg, dst_reg)); 700 break; 701 case 32: 702 /* emit 'bswap eax' to swap lower 4 bytes */ 703 if (is_ereg(dst_reg)) 704 EMIT2(0x41, 0x0F); 705 else 706 EMIT1(0x0F); 707 EMIT1(add_1reg(0xC8, dst_reg)); 708 break; 709 case 64: 710 /* emit 'bswap rax' to swap 8 bytes */ 711 EMIT3(add_1mod(0x48, dst_reg), 0x0F, 712 add_1reg(0xC8, dst_reg)); 713 break; 714 } 715 break; 716 717 case BPF_ALU | BPF_END | BPF_FROM_LE: 718 switch (imm32) { 719 case 16: 720 /* emit 'movzwl eax, ax' to zero extend 16-bit 721 * into 64 bit 722 */ 723 if (is_ereg(dst_reg)) 724 EMIT3(0x45, 0x0F, 0xB7); 725 else 726 EMIT2(0x0F, 0xB7); 727 EMIT1(add_2reg(0xC0, dst_reg, dst_reg)); 728 break; 729 case 32: 730 /* emit 'mov eax, eax' to clear upper 32-bits */ 731 if (is_ereg(dst_reg)) 732 EMIT1(0x45); 733 EMIT2(0x89, add_2reg(0xC0, dst_reg, dst_reg)); 734 break; 735 case 64: 736 /* nop */ 737 break; 738 } 739 break; 740 741 /* ST: *(u8*)(dst_reg + off) = imm */ 742 case BPF_ST | BPF_MEM | BPF_B: 743 if (is_ereg(dst_reg)) 744 EMIT2(0x41, 0xC6); 745 else 746 EMIT1(0xC6); 747 goto st; 748 case BPF_ST | BPF_MEM | BPF_H: 749 if (is_ereg(dst_reg)) 750 EMIT3(0x66, 0x41, 0xC7); 751 else 752 EMIT2(0x66, 0xC7); 753 goto st; 754 case BPF_ST | BPF_MEM | BPF_W: 755 if (is_ereg(dst_reg)) 756 EMIT2(0x41, 0xC7); 757 else 758 EMIT1(0xC7); 759 goto st; 760 case BPF_ST | BPF_MEM | BPF_DW: 761 EMIT2(add_1mod(0x48, dst_reg), 0xC7); 762 763 st: if (is_imm8(insn->off)) 764 EMIT2(add_1reg(0x40, dst_reg), insn->off); 765 else 766 EMIT1_off32(add_1reg(0x80, dst_reg), insn->off); 767 768 EMIT(imm32, bpf_size_to_x86_bytes(BPF_SIZE(insn->code))); 769 break; 770 771 /* STX: *(u8*)(dst_reg + off) = src_reg */ 772 case BPF_STX | BPF_MEM | BPF_B: 773 /* emit 'mov byte ptr [rax + off], al' */ 774 if (is_ereg(dst_reg) || is_ereg(src_reg) || 775 /* have to add extra byte for x86 SIL, DIL regs */ 776 src_reg == BPF_REG_1 || src_reg == BPF_REG_2) 777 EMIT2(add_2mod(0x40, dst_reg, src_reg), 0x88); 778 else 779 EMIT1(0x88); 780 goto stx; 781 case BPF_STX | BPF_MEM | BPF_H: 782 if (is_ereg(dst_reg) || is_ereg(src_reg)) 783 EMIT3(0x66, add_2mod(0x40, dst_reg, src_reg), 0x89); 784 else 785 EMIT2(0x66, 0x89); 786 goto stx; 787 case BPF_STX | BPF_MEM | BPF_W: 788 if (is_ereg(dst_reg) || is_ereg(src_reg)) 789 EMIT2(add_2mod(0x40, dst_reg, src_reg), 0x89); 790 else 791 EMIT1(0x89); 792 goto stx; 793 case BPF_STX | BPF_MEM | BPF_DW: 794 EMIT2(add_2mod(0x48, dst_reg, src_reg), 0x89); 795 stx: if (is_imm8(insn->off)) 796 EMIT2(add_2reg(0x40, dst_reg, src_reg), insn->off); 797 else 798 EMIT1_off32(add_2reg(0x80, dst_reg, src_reg), 799 insn->off); 800 break; 801 802 /* LDX: dst_reg = *(u8*)(src_reg + off) */ 803 case BPF_LDX | BPF_MEM | BPF_B: 804 /* emit 'movzx rax, byte ptr [rax + off]' */ 805 EMIT3(add_2mod(0x48, src_reg, dst_reg), 0x0F, 0xB6); 806 goto ldx; 807 case BPF_LDX | BPF_MEM | BPF_H: 808 /* emit 'movzx rax, word ptr [rax + off]' */ 809 EMIT3(add_2mod(0x48, src_reg, dst_reg), 0x0F, 0xB7); 810 goto ldx; 811 case BPF_LDX | BPF_MEM | BPF_W: 812 /* emit 'mov eax, dword ptr [rax+0x14]' */ 813 if (is_ereg(dst_reg) || is_ereg(src_reg)) 814 EMIT2(add_2mod(0x40, src_reg, dst_reg), 0x8B); 815 else 816 EMIT1(0x8B); 817 goto ldx; 818 case BPF_LDX | BPF_MEM | BPF_DW: 819 /* emit 'mov rax, qword ptr [rax+0x14]' */ 820 EMIT2(add_2mod(0x48, src_reg, dst_reg), 0x8B); 821 ldx: /* if insn->off == 0 we can save one extra byte, but 822 * special case of x86 r13 which always needs an offset 823 * is not worth the hassle 824 */ 825 if (is_imm8(insn->off)) 826 EMIT2(add_2reg(0x40, src_reg, dst_reg), insn->off); 827 else 828 EMIT1_off32(add_2reg(0x80, src_reg, dst_reg), 829 insn->off); 830 break; 831 832 /* STX XADD: lock *(u32*)(dst_reg + off) += src_reg */ 833 case BPF_STX | BPF_XADD | BPF_W: 834 /* emit 'lock add dword ptr [rax + off], eax' */ 835 if (is_ereg(dst_reg) || is_ereg(src_reg)) 836 EMIT3(0xF0, add_2mod(0x40, dst_reg, src_reg), 0x01); 837 else 838 EMIT2(0xF0, 0x01); 839 goto xadd; 840 case BPF_STX | BPF_XADD | BPF_DW: 841 EMIT3(0xF0, add_2mod(0x48, dst_reg, src_reg), 0x01); 842 xadd: if (is_imm8(insn->off)) 843 EMIT2(add_2reg(0x40, dst_reg, src_reg), insn->off); 844 else 845 EMIT1_off32(add_2reg(0x80, dst_reg, src_reg), 846 insn->off); 847 break; 848 849 /* call */ 850 case BPF_JMP | BPF_CALL: 851 func = (u8 *) __bpf_call_base + imm32; 852 jmp_offset = func - (image + addrs[i]); 853 if (seen_ld_abs) { 854 reload_skb_data = bpf_helper_changes_pkt_data(func); 855 if (reload_skb_data) { 856 EMIT1(0x57); /* push %rdi */ 857 jmp_offset += 22; /* pop, mov, sub, mov */ 858 } else { 859 EMIT2(0x41, 0x52); /* push %r10 */ 860 EMIT2(0x41, 0x51); /* push %r9 */ 861 /* need to adjust jmp offset, since 862 * pop %r9, pop %r10 take 4 bytes after call insn 863 */ 864 jmp_offset += 4; 865 } 866 } 867 if (!imm32 || !is_simm32(jmp_offset)) { 868 pr_err("unsupported bpf func %d addr %p image %p\n", 869 imm32, func, image); 870 return -EINVAL; 871 } 872 EMIT1_off32(0xE8, jmp_offset); 873 if (seen_ld_abs) { 874 if (reload_skb_data) { 875 EMIT1(0x5F); /* pop %rdi */ 876 emit_load_skb_data_hlen(&prog); 877 } else { 878 EMIT2(0x41, 0x59); /* pop %r9 */ 879 EMIT2(0x41, 0x5A); /* pop %r10 */ 880 } 881 } 882 break; 883 884 case BPF_JMP | BPF_TAIL_CALL: 885 emit_bpf_tail_call(&prog); 886 break; 887 888 /* cond jump */ 889 case BPF_JMP | BPF_JEQ | BPF_X: 890 case BPF_JMP | BPF_JNE | BPF_X: 891 case BPF_JMP | BPF_JGT | BPF_X: 892 case BPF_JMP | BPF_JLT | BPF_X: 893 case BPF_JMP | BPF_JGE | BPF_X: 894 case BPF_JMP | BPF_JLE | BPF_X: 895 case BPF_JMP | BPF_JSGT | BPF_X: 896 case BPF_JMP | BPF_JSLT | BPF_X: 897 case BPF_JMP | BPF_JSGE | BPF_X: 898 case BPF_JMP | BPF_JSLE | BPF_X: 899 /* cmp dst_reg, src_reg */ 900 EMIT3(add_2mod(0x48, dst_reg, src_reg), 0x39, 901 add_2reg(0xC0, dst_reg, src_reg)); 902 goto emit_cond_jmp; 903 904 case BPF_JMP | BPF_JSET | BPF_X: 905 /* test dst_reg, src_reg */ 906 EMIT3(add_2mod(0x48, dst_reg, src_reg), 0x85, 907 add_2reg(0xC0, dst_reg, src_reg)); 908 goto emit_cond_jmp; 909 910 case BPF_JMP | BPF_JSET | BPF_K: 911 /* test dst_reg, imm32 */ 912 EMIT1(add_1mod(0x48, dst_reg)); 913 EMIT2_off32(0xF7, add_1reg(0xC0, dst_reg), imm32); 914 goto emit_cond_jmp; 915 916 case BPF_JMP | BPF_JEQ | BPF_K: 917 case BPF_JMP | BPF_JNE | BPF_K: 918 case BPF_JMP | BPF_JGT | BPF_K: 919 case BPF_JMP | BPF_JLT | BPF_K: 920 case BPF_JMP | BPF_JGE | BPF_K: 921 case BPF_JMP | BPF_JLE | BPF_K: 922 case BPF_JMP | BPF_JSGT | BPF_K: 923 case BPF_JMP | BPF_JSLT | BPF_K: 924 case BPF_JMP | BPF_JSGE | BPF_K: 925 case BPF_JMP | BPF_JSLE | BPF_K: 926 /* cmp dst_reg, imm8/32 */ 927 EMIT1(add_1mod(0x48, dst_reg)); 928 929 if (is_imm8(imm32)) 930 EMIT3(0x83, add_1reg(0xF8, dst_reg), imm32); 931 else 932 EMIT2_off32(0x81, add_1reg(0xF8, dst_reg), imm32); 933 934 emit_cond_jmp: /* convert BPF opcode to x86 */ 935 switch (BPF_OP(insn->code)) { 936 case BPF_JEQ: 937 jmp_cond = X86_JE; 938 break; 939 case BPF_JSET: 940 case BPF_JNE: 941 jmp_cond = X86_JNE; 942 break; 943 case BPF_JGT: 944 /* GT is unsigned '>', JA in x86 */ 945 jmp_cond = X86_JA; 946 break; 947 case BPF_JLT: 948 /* LT is unsigned '<', JB in x86 */ 949 jmp_cond = X86_JB; 950 break; 951 case BPF_JGE: 952 /* GE is unsigned '>=', JAE in x86 */ 953 jmp_cond = X86_JAE; 954 break; 955 case BPF_JLE: 956 /* LE is unsigned '<=', JBE in x86 */ 957 jmp_cond = X86_JBE; 958 break; 959 case BPF_JSGT: 960 /* signed '>', GT in x86 */ 961 jmp_cond = X86_JG; 962 break; 963 case BPF_JSLT: 964 /* signed '<', LT in x86 */ 965 jmp_cond = X86_JL; 966 break; 967 case BPF_JSGE: 968 /* signed '>=', GE in x86 */ 969 jmp_cond = X86_JGE; 970 break; 971 case BPF_JSLE: 972 /* signed '<=', LE in x86 */ 973 jmp_cond = X86_JLE; 974 break; 975 default: /* to silence gcc warning */ 976 return -EFAULT; 977 } 978 jmp_offset = addrs[i + insn->off] - addrs[i]; 979 if (is_imm8(jmp_offset)) { 980 EMIT2(jmp_cond, jmp_offset); 981 } else if (is_simm32(jmp_offset)) { 982 EMIT2_off32(0x0F, jmp_cond + 0x10, jmp_offset); 983 } else { 984 pr_err("cond_jmp gen bug %llx\n", jmp_offset); 985 return -EFAULT; 986 } 987 988 break; 989 990 case BPF_JMP | BPF_JA: 991 jmp_offset = addrs[i + insn->off] - addrs[i]; 992 if (!jmp_offset) 993 /* optimize out nop jumps */ 994 break; 995 emit_jmp: 996 if (is_imm8(jmp_offset)) { 997 EMIT2(0xEB, jmp_offset); 998 } else if (is_simm32(jmp_offset)) { 999 EMIT1_off32(0xE9, jmp_offset); 1000 } else { 1001 pr_err("jmp gen bug %llx\n", jmp_offset); 1002 return -EFAULT; 1003 } 1004 break; 1005 1006 case BPF_LD | BPF_IND | BPF_W: 1007 func = sk_load_word; 1008 goto common_load; 1009 case BPF_LD | BPF_ABS | BPF_W: 1010 func = CHOOSE_LOAD_FUNC(imm32, sk_load_word); 1011 common_load: 1012 ctx->seen_ld_abs = seen_ld_abs = true; 1013 jmp_offset = func - (image + addrs[i]); 1014 if (!func || !is_simm32(jmp_offset)) { 1015 pr_err("unsupported bpf func %d addr %p image %p\n", 1016 imm32, func, image); 1017 return -EINVAL; 1018 } 1019 if (BPF_MODE(insn->code) == BPF_ABS) { 1020 /* mov %esi, imm32 */ 1021 EMIT1_off32(0xBE, imm32); 1022 } else { 1023 /* mov %rsi, src_reg */ 1024 EMIT_mov(BPF_REG_2, src_reg); 1025 if (imm32) { 1026 if (is_imm8(imm32)) 1027 /* add %esi, imm8 */ 1028 EMIT3(0x83, 0xC6, imm32); 1029 else 1030 /* add %esi, imm32 */ 1031 EMIT2_off32(0x81, 0xC6, imm32); 1032 } 1033 } 1034 /* skb pointer is in R6 (%rbx), it will be copied into 1035 * %rdi if skb_copy_bits() call is necessary. 1036 * sk_load_* helpers also use %r10 and %r9d. 1037 * See bpf_jit.S 1038 */ 1039 if (seen_ax_reg) 1040 /* r10 = skb->data, mov %r10, off32(%rbx) */ 1041 EMIT3_off32(0x4c, 0x8b, 0x93, 1042 offsetof(struct sk_buff, data)); 1043 EMIT1_off32(0xE8, jmp_offset); /* call */ 1044 break; 1045 1046 case BPF_LD | BPF_IND | BPF_H: 1047 func = sk_load_half; 1048 goto common_load; 1049 case BPF_LD | BPF_ABS | BPF_H: 1050 func = CHOOSE_LOAD_FUNC(imm32, sk_load_half); 1051 goto common_load; 1052 case BPF_LD | BPF_IND | BPF_B: 1053 func = sk_load_byte; 1054 goto common_load; 1055 case BPF_LD | BPF_ABS | BPF_B: 1056 func = CHOOSE_LOAD_FUNC(imm32, sk_load_byte); 1057 goto common_load; 1058 1059 case BPF_JMP | BPF_EXIT: 1060 if (seen_exit) { 1061 jmp_offset = ctx->cleanup_addr - addrs[i]; 1062 goto emit_jmp; 1063 } 1064 seen_exit = true; 1065 /* update cleanup_addr */ 1066 ctx->cleanup_addr = proglen; 1067 /* mov rbx, qword ptr [rbp+0] */ 1068 EMIT4(0x48, 0x8B, 0x5D, 0); 1069 /* mov r13, qword ptr [rbp+8] */ 1070 EMIT4(0x4C, 0x8B, 0x6D, 8); 1071 /* mov r14, qword ptr [rbp+16] */ 1072 EMIT4(0x4C, 0x8B, 0x75, 16); 1073 /* mov r15, qword ptr [rbp+24] */ 1074 EMIT4(0x4C, 0x8B, 0x7D, 24); 1075 1076 /* add rbp, AUX_STACK_SPACE */ 1077 EMIT4(0x48, 0x83, 0xC5, AUX_STACK_SPACE); 1078 EMIT1(0xC9); /* leave */ 1079 EMIT1(0xC3); /* ret */ 1080 break; 1081 1082 default: 1083 /* By design x64 JIT should support all BPF instructions 1084 * This error will be seen if new instruction was added 1085 * to interpreter, but not to JIT 1086 * or if there is junk in bpf_prog 1087 */ 1088 pr_err("bpf_jit: unknown opcode %02x\n", insn->code); 1089 return -EINVAL; 1090 } 1091 1092 ilen = prog - temp; 1093 if (ilen > BPF_MAX_INSN_SIZE) { 1094 pr_err("bpf_jit: fatal insn size error\n"); 1095 return -EFAULT; 1096 } 1097 1098 if (image) { 1099 if (unlikely(proglen + ilen > oldproglen)) { 1100 pr_err("bpf_jit: fatal error\n"); 1101 return -EFAULT; 1102 } 1103 memcpy(image + proglen, temp, ilen); 1104 } 1105 proglen += ilen; 1106 addrs[i] = proglen; 1107 prog = temp; 1108 } 1109 return proglen; 1110 } 1111 1112 struct bpf_prog *bpf_int_jit_compile(struct bpf_prog *prog) 1113 { 1114 struct bpf_binary_header *header = NULL; 1115 struct bpf_prog *tmp, *orig_prog = prog; 1116 int proglen, oldproglen = 0; 1117 struct jit_context ctx = {}; 1118 bool tmp_blinded = false; 1119 u8 *image = NULL; 1120 int *addrs; 1121 int pass; 1122 int i; 1123 1124 if (!bpf_jit_enable) 1125 return orig_prog; 1126 1127 tmp = bpf_jit_blind_constants(prog); 1128 /* If blinding was requested and we failed during blinding, 1129 * we must fall back to the interpreter. 1130 */ 1131 if (IS_ERR(tmp)) 1132 return orig_prog; 1133 if (tmp != prog) { 1134 tmp_blinded = true; 1135 prog = tmp; 1136 } 1137 1138 addrs = kmalloc(prog->len * sizeof(*addrs), GFP_KERNEL); 1139 if (!addrs) { 1140 prog = orig_prog; 1141 goto out; 1142 } 1143 1144 /* Before first pass, make a rough estimation of addrs[] 1145 * each bpf instruction is translated to less than 64 bytes 1146 */ 1147 for (proglen = 0, i = 0; i < prog->len; i++) { 1148 proglen += 64; 1149 addrs[i] = proglen; 1150 } 1151 ctx.cleanup_addr = proglen; 1152 1153 /* JITed image shrinks with every pass and the loop iterates 1154 * until the image stops shrinking. Very large bpf programs 1155 * may converge on the last pass. In such case do one more 1156 * pass to emit the final image 1157 */ 1158 for (pass = 0; pass < 10 || image; pass++) { 1159 proglen = do_jit(prog, addrs, image, oldproglen, &ctx); 1160 if (proglen <= 0) { 1161 image = NULL; 1162 if (header) 1163 bpf_jit_binary_free(header); 1164 prog = orig_prog; 1165 goto out_addrs; 1166 } 1167 if (image) { 1168 if (proglen != oldproglen) { 1169 pr_err("bpf_jit: proglen=%d != oldproglen=%d\n", 1170 proglen, oldproglen); 1171 prog = orig_prog; 1172 goto out_addrs; 1173 } 1174 break; 1175 } 1176 if (proglen == oldproglen) { 1177 header = bpf_jit_binary_alloc(proglen, &image, 1178 1, jit_fill_hole); 1179 if (!header) { 1180 prog = orig_prog; 1181 goto out_addrs; 1182 } 1183 } 1184 oldproglen = proglen; 1185 } 1186 1187 if (bpf_jit_enable > 1) 1188 bpf_jit_dump(prog->len, proglen, pass + 1, image); 1189 1190 if (image) { 1191 bpf_flush_icache(header, image + proglen); 1192 bpf_jit_binary_lock_ro(header); 1193 prog->bpf_func = (void *)image; 1194 prog->jited = 1; 1195 prog->jited_len = proglen; 1196 } else { 1197 prog = orig_prog; 1198 } 1199 1200 out_addrs: 1201 kfree(addrs); 1202 out: 1203 if (tmp_blinded) 1204 bpf_jit_prog_release_other(prog, prog == orig_prog ? 1205 tmp : orig_prog); 1206 return prog; 1207 } 1208